1. Field of the Invention
This invention relates generally to rectal specula, and more particularly, to a speculum for use with a colonic lavage machine.
2. Description of the Prior Art
Devices are known for lavaging the lower intestinal tract of patients suffering from colitis and other similar ailments. Examples of such devices can be found in U.S. Pat. No. 2,826,197 to Leonard, U.S. Pat. No. 3,771,522 to Waysilk et al, and U.S. Pat. No. 4,190,059 to Holt. These devices commonly employ a speculum for directing treating fluids into patient's colon and subsequently allowing the discharge of fluidized waste matter.
Typically, the rectal specula used with the above devices comprise a pair of concentric tubes, including an inlet tube which carries water into the patient's rectum and colon, and a discharge tube which allows fluidized waste matter to flow out of the patient's body. In addition, in order to faciliate insertion of the speculum in the patient's rectal canal, and to decrease the patient's discomfort and possible pain as well as to avoid possible damage to the patient's intestinal tract, the speculum is usually used in combination with an obturator. Typically, an obturator comprises an elongated rod provided with a tapered, round exterior portion at one end, and a handle portion at the opposite end. Normally, the obturator is inserted from the proximal end of the speculum through the hollow interior to extend through the distal end thereof in order to facilitate insertion of the speculum into the patient's rectum, and is then removed from the speculum by use of the handle.
The conventional specula as described above suffer from a number of drawbacks. One problem is that the concentric tube structure makes the specula difficult and expensive to manufacture, as well as inconvenient to clean and maintain. A second problem is that the process of removing the obturator and attaching a discharge hose or conduit to the outlet end of the speculum can be painful to the patient since the inlet end of the speculum is free to rock or slip in the patient's rectum while the hose is being attached.
In an attempt to solve the first of these problems, one speculum has been introduced which does away with the conventional concentric tube structure. This speculum is shown in U.S. Pat. No. Des. 228,204 to Holt. The Holt speculum comprises a pair of intersecting tubes including an unobstructed main tube having a distal end adapted for insertion in a patient's rectum and a proximal or discharge end adapted for connection to a waste removal hose, and an inlet tube connectible to a source of water for permitting injection of water into the main tube. The inlet tube is considerably smaller in diameter than the main tube and is disposed at an acute angle to the discharge end of the main tube. This angle causes a slight inlet current in the direction of the patient's colon when the lavaging machine is in operation.
Once the Holt speculum has been inserted into the patient's body, with an inlet hose having been previously connected to the inlet tube of the speculum, a waste removal hose must be subsequently connected to the proximal end of the main tube due to the need for removing the obturator. Water or other treating fluid from an external source is then allowed to travel through the inlet hose and inlet tube and fills up the main tube and waste removal hose until a sufficient back pressure has been built up to direct the fluid into the patient's lower intestine. Once the fluid pressure in the intestine is equal to or greater than the pressure in the main tube and the waste discharge tube, the water and fluidized waste matter in the intestine is discharged through the speculum. The problem with the Holt structure, however, is that because of the orientation of inlet tube relative to the main tube of the speculum, the discharged waste matter must flow counter to the direction of the inlet current. This means that the pressure on the patient's intestine is relieved much more slowly and less effectively than in a speculum in which the discharge material does not have to fight a counter current. As a result, the patient suffers greater pain and discomfort than is necessary.
Therefore, a need exists for a new and improved rectal speculum which overcomes some of the problems and shortcomings of the prior art.